The president of the Cop28 climate summit will continue with his oil company’s record investment in oil and gas production, despite coordinating a global deal to “transition away” from fossil fuels.

Sultan Al Jaber, who is also the chief executive of the United Arab Emirates’ national oil and gas company, Adnoc, told the Guardian the company had to satisfy demand for fossil fuels.

“My approach is very simple: it is that we will continue to act as a responsible, reliable supplier of low-carbon energy, and the world will need the lowest-carbon barrels at the lowest cost,” he said, arguing that Adnoc’s hydrocarbons are lower carbon because they are extracted efficiently and with less leakage than other sources.

“At the end of the day, remember, it is the demand that will decide and dictate what sort of energy source will help meet the growing global energy requirements,” he added.

He referred to the findings of the Intergovernmental Panel on Climate Change that the world will still need a small amount of fossil fuel in 2050, even when reaching net zero greenhouse gas emissions, which is required to limit global temperature rises to 1.5C (2.7F) above pre-industrial levels.

Al Jaber said his investment plans were viable within the 1.5C limit. “The world continues to need low-carbon oil and gas and low-cost oil and gas,” he said. “When the demand stops, that’s a completely different story. What we need to do right now is to decarbonise the current energy system, while we build the new energy system.”

Adnoc is planning a $150bn investment (£120m) over seven years in oil and gas, which Al Jaber said would maintain current production levels rather than increase output. He said Adnoc was forgoing much of its potential extraction.

“We have the fifth largest oil reserves in the world but we are not harnessing these resources,” he said in an exclusive interview after the summit.

Al Jaber was widely praised by delegates at the Cop28 summit, which ended on Wednesday morning with a global agreement calling on countries to “contribute to … transitioning away from fossil fuels in energy systems, in a just, orderly and equitable manner, accelerating action in this critical decade, so as to achieve net zero by 2050 in keeping with the science.”

It marked the first time in 30 years of climate talks that a global resolution had been made addressing the future of all fossil fuels. The deal was acknowledged as nowhere near enough to stave off the worst impacts of the climate crisis, and was criticised by developing countries for failing to provide them with assurances of much-needed finance, but was widely hailed as an important step.

Despite widespread consternation earlier this year over his dual role as head of Cop28 and of Adnoc, Al Jaber proved a popular Cop president. Developing countries at the summit said Al Jaber was listening and responding to their concerns, while rich countries spoke well of his determination to forge a consensus deal.

Al Jaber, who before taking on the Adnoc role co-founded the UAE government-backed renewable energy company Masdar in 2006, told the Guardian: “I am committed to the transition [to a low-carbon world]. This is something I have personally worked on for more than 18 years now. I know energy dynamics and energy economics. I’m an engineer.”

He argued that his position as a businessman and oil company chief had helped him bring off the surprise deal. “Through my presidency, we proved and we showed the world that having an industry leadership of a Cop was not a weakness. In fact, it was a strength, it was an advantage,” he said.